What is the primary biochemical consequence of mutations in the CFTR gene located on chromosome 7, which causes cystic fibrosis?

💡 Solution & Explanation

Cystic fibrosis is caused by mutations in the cystic fibrosis transmembrane conductance regulator gene, which encodes an ATP-gated chloride channel necessary for maintaining fluid and ion balance across epithelial cell membranes. Defective transport prevents proper chloride and water movement, producing abnormally thick secretions that clog respiratory and digestive tracts. Abnormal hemoglobin beta chains characterize sickle cell anemia rather than cystic fibrosis. Demyelinating peripheral neuropathies involve distinct genetic loci unrelated to the CFTR transporter.